Chemical Reactions Unit 7 1
Chemical Equations 2 FeO 2 (s) + 2 H 2 (g) Fe (s) + 2 H 2 O (l) NaCl (aq) + AgNO 3 (aq) AgCl (s) + NaNO 3 (aq) Symbol Found in Chemical Equation Physical Meaning Produces - equivalent to an equal sign in an algebraic expression +Reacts with or is produced with (s)Compound is a solid (l)Compound is a liquid (g)Compound is a gas (aq)Compound is aqueous (dissolved in water Reactants Products
Chemical Equations 3 A chemical equation is a representation for a chemical reaction that uses chemical symbols and chemical formulas instead of words to describe the change that occurs in a chemical reaction. 2 Mg + O 2 MgOMg + Cl 2 MgCl 2 Reactants Products Conservation of Matter! Remember that atoms cannot be created or destroyed!
Balancing Chemical Equations 4 CH 4 + O 2 CO 2 + H 2 OFe 3 O 4 + H 2 Fe + H 2 O Ca + N 2 Ca 3 N 2 C 4 H 10 + O 2 CO 2 + H 2 O NH 4 NO 3 N 2 + O 2 + H 2 O Remember that atoms cannot be created or destroyed! SCl 2 + NaF SF 4 + S 2 Cl 2 + NaCl
Chemical Equations 5 Synthesis Reactions A single product is produced from 2 or more reactants X + Y Z SO 3 + H 2 O H 2 SO 4 Decomposition Reactions A single reactant is converted into 2 or more products Z X + Y H 2 SO 4 SO 3 + H 2 O
Chemical Equations 6 Single Replacement Reactions One element within a compound is replaced with another element XY + Z ZY + X H 2 SO 4 + Mg 2+ MgSO H + Double Replacement Reactions 2 compounds switch parts with each other to form two new compounds AB + XY AX + BY MgSO 4 + CaCO 3 CaSO 4 + MgCO 3
Combustion Reactions A substance reacts with O 2 (typically with the help of a flame) 2 C 4 H O 2 8 CO H 2 O Chemical Equations 7